Fig. 6.

Increased value-free random exploration in ADHD. (a) Value-free random exploration (as captured by the model parameter ϵ) was linked to ADHD symptom scores in this population sample. A score >70 (dashed vertical line) is considered very elevated (Conners, 2008). Each dot represents one subject. White: children, light blue: early adolescents, dark blue: late adolescents. (b) Further analysis revealed an excessive usage of value-free random exploration specifically in the long horizon in the very elevated ADHD score group (subjects with an ADHD score ≥70). Black cross: score-by-horizon interaction. Black line: pairwise t-tests. Overall, our results suggest an overuse of value-free random exploration in ADHD. **p < 0.01; ns = p > 0.05. Data are mean ± 1 SEM and each line represent one subject